Very weird problem with dc driver

[Brandon Fosdick]

David Malone wrote:
> On Thu, Dec 25, 2003 at 01:37:32AM -0600, Shawn K. Quinn wrote:
> 
>>Oh, I also found this little gem after the first power-off/power-on 
>>reboot:
>>
>>Dec 25 00:32:58 xevious /kernel: dc0: TX underrun -- increasing TX 
>>threshold
> 
> 
> In general, you don't need to worry about these, they are just the driver
> adjusting itself to the speed of your card/motherboard. You may see a few
> of them when the machine is first busy after boot, and then they should
> probably stop.

I have a machine running 4.9 and using the dc driver (Netgear FA310TX) 
that gets lots of these messages. For the most part they happen when the 
network cable is unplugged, but I also get a number of them randomly. 
They're not entirely harmless either since the umass driver seems to be 
affected. If one of the messages pops up while transferring to/from a 
usb drive the transfer stalls in poll (according to top) and any 
subsequent attempt to access (ls,cd, etc) either disk involved in the 
transfer also gets locked in the poll state.

I can't provide much more info since the machine is on the other side of 
the country and not on the net anymore, but this isn't the first time 
I've had this problem. And I think I saw something about it on a mailing 
list a long time ago....

http://groups.google.com/groups?q=freebsd+netgear+310tx+underrun&hl=en&lr=&ie=UTF-8&oe=UTF-8&selm=200001070505.VAA01104_mordred.cs.ucla.edu%40ns.sol.net&rnum=1
http://groups.google.com/groups?hl=en&lr=&ie=UTF-8&oe=UTF-8&threadm=3BEBCA14.8FFC9781_wgops.com%40ns.sol.net&rnum=2&prev=/groups%3Fq%3Dfreebsd%2Bdc%2Bunderrun%26hl%3Den%26lr%3D%26ie%3DUTF-8%26oe%3DUTF-8%26selm%3D3BEBCA14.8FFC9781_wgops.com%2540ns.sol.net%26rnum%3D2
http://groups.google.com/groups?q=freebsd+dc+underrun&hl=en&lr=&ie=UTF-8&oe=UTF-8&selm=3BB811A5.F301F9FD%40pacbell.net&rnum=3
http://groups.google.com/groups?hl=en&lr=&ie=UTF-8&oe=UTF-8&threadm=20020225203050.U21168-100000_patrocles.silby.com%40ns.sol.net&rnum=9&prev=/groups%3Fq%3Dfreebsd%2Bdc%2Bunderrun%26hl%3Den%26lr%3D%26ie%3DUTF-8%26oe%3DUTF-8%26selm%3D20020225203050.U21168-100000_patrocles.silby.com%2540ns.sol.net%26rnum%3D9
http://groups.google.com/groups?hl=en&lr=&ie=UTF-8&oe=UTF-8&threadm=20020226101713.S25801-100000_patrocles.silby.com%40ns.sol.net&rnum=8&prev=/groups%3Fq%3Dfreebsd%2Bdc%2Bunderrun%26hl%3Den%26lr%3D%26ie%3DUTF-8%26oe%3DUTF-8%26selm%3D20020226101713.S25801-100000_patrocles.silby.com%2540ns.sol.net%26rnum%3D8

Google found a few other threads but I don't feel like listing them.

-- 
Brandon Fosdick
http://www.terranspace.org